2013-05-30 - The first large-capacity, battery-powered bus on show at a major international conference on transportation in the Swiss city of Geneva. It operates without overhead lines and recharges at selected bus stops in a mere 15 seconds. ABB has developed the core technology for this project including the onboard traction equipment and the new type of fully automatic flash charging system.

The electric powered articulated bus project, named TOSA after the four member partnership between TPG (Geneva’s public transport company), OPI (the Office for the Promotion of Industries and Technologies), SIG (the Geneva power utility) and ABB, looks like a regular trolley bus, except when you look on the roof. Instead of the usual trolley poles to overhead lines, this bus has a laser controlled moving arm that connects to an overhead receptacle integrated into the bus shelter. The docking procedure is incredibly quick, it takes place in less than a second. When the time spent at a stop is just 15 seconds, it is essential not to lose time docking.

As the bus approaches the stop, the fixed overhead receptacle is detected and the rooftop contact begins to align itself laterally to it. Once this is achieved, the charging arm rises up from the bus and makes contact. A safety check ensures that a proper connection is made with the stationary bus before voltage is applied.

The flash charging technology allows the onboard batteries to be fed with a 15 second boost of energy at stops along the route. At the end of the bus line a 3 to 4 minute ultrafast-charge is made to fully recharge the batteries. Thanks to an innovative electrical drive system, the energy can be stored in compact batteries along with the vehicle’s braking energy. The braking energy can be used to power the motors or can be consumed inside the vehicle.

The great advantage of this system, like all electric transport, is that there are no local carbon dioxide emissions or other pollutants in the city, but what makes this system even better is that the electric power used on this bus route is wholly hydro-generated, making it an ideal solution for Geneva’s sustainable mass transportation services to the public. Moreover the buses no longer need overhead lines, which helps reduce visual pollution while providing greater route flexibility.

Project with four Geneva partners
The project was conceived with a view to easing traffic congestion in Geneva. In October 2010 a study to determine the feasibility of flash charging electric buses for a municipal transportation system was initiated. The project proper was started in 2011 and has developed at such a rapid pace that the TOSA bus was ready to be unveiled officially at the 60th UITP World Congress and Mobility & City Transport Exhibition, which was held this week in Geneva from May 26 to 30.

The articulated bus, which can carry 133 passengers, made its maiden trip after it was inaugurated by the Swiss Transport Minister, Doris Leuthard, who hailed the bus as a brilliant invention. The demo model of the electric bus will operate between Geneva Airport and the Palexpo exhibition center to gather performance data over a 1.8 kilometer segment of bus route 5, a city route with typical levels of traffic congestion.